The Aspire S3-391 has a better processor family than most laptops that are a similar age to it. This notebook PC has an Intel Core i3-2xxx processor family, whereas most portable PCs that are a similar age to it have an Intel Core i5 processor family.
This notebook PC's processor family (Intel Core i3-2xxx) is in fact the worst processor family across all ultrabooks that were released around the same time as the Aspire S3-391.
An Intel Core i7-3xxx processor family is the best processor family across similar types of notebook PC.
If the processor family of this notebook PC is not good enough for you then you might also want to consider the Samsung 540U3C (Intel Core i3-3xxx).